It used to be that short tracks were the guaranteed place for the bumping, banging and blown tempers. It's now shifted to road courses, specifically Sonoma, where more than a few drivers will likely be raging mad by the end of Sunday's race.

"I think this has turned into the most no-holds-barred, crazy, people-running-into-each-other race, more so than any of the short tracks we go to now," said Sprint Cup Series points leader Matt Kenseth.

NASCAR's last two visits to the winding road course in Northern California wine country have been demolition derbies. Jeff Gordon was the bad guy in 2010, when he tangled on track with at least four drivers in a race he deemed a "disaster — just one of those terrible days where I made a lot of mistakes, no doubt made a lot of people unhappy."

The lasting image from last year's stop at the 12-turn, 1.99-mile picturesque track was of Tony Stewart's car backed into and suspended high on a wall of tires, where he landed after Brian Vickers intentionally spun him as payback for earlier contact. But tempers were flaring all over the garage after the race. Juan Pablo Montoya left mad at Brad Keselowski, Kasey Kahne was angry with Montoya, and Joey Logano's parting shot for road course ace Robby Gordon was that "he drives like a moron every week."

Denny Hamlin, who said last year he'd been "Dinger'd" after he was involved in a wreck with AJ Allmendinger, said all driver etiquette seems to be out the window when the series shifts to Sonoma.

"It just seems like people don't give each other room like they used to and everyone is just a little bit more aggressive," Hamlin said. "I think people talk about driver ethics and things like that — this is a very gray race track when it comes to that. I think people can get away with a little bit more, maybe pay some guys back for things that happen at other tracks.

"Typically, at this race track, because speeds are so low, the risk of injuring someone is slim to none."

Jamie McMurray, an innocent victim in last year's Stewart-Vickers clash, had a much simpler explanation: "The wrecks are happening from people being idiots," he said.

"You can't be the guy that's run 17th all day, and on the last restart expect that you are going to pass six rows of cars in turn seven. That's what happens here every single year," McMurray added. "Somebody just does something silly. Most of the time the wrecks here just happen from people losing their mind."

Double-file restarts are likely the overwhelming cause of the problem.

Because Sonoma has a limited number of passing zones, drivers tend to try to make up as much ground as possible on the restarts. It leads to aggressive moves on a tight course, and if a driver fails to move through the field as he had hoped, he can get stuck behind a slower car and lose all patience in trying to gain position.

So for all the attention Bristol and Martinsville and Richmond receive as the places where mayhem happens, Kevin Harvick believes it's Sonoma that has moved to the top of the list of tracks where drivers tangle.

"It has been for the last few years," Harvick said. "I think a lot of that comes from the double-file restarts, and I think it escalates as the day goes on. When you get those opportunities to pass, you have to dive in there and take that opportunity. Sometimes you make a mistake and get into a guy and get into his door or whatever the case may be."

There are probably only three true passing zones on the course — in turns 3, 7 and 11 — but drivers don't seem to wait anymore for those opportunities.

"I started road course racing however long ago it was, and there was always road course etiquette," Kenseth said. "You would only pass in certain zones, and when people got alongside you to pass in those zones, you would drop back and fall in line and go on. You would really race the race track the entire race and race the fuel mileage and tires and try to be in position.

"I think the two-wide restarts has really thrown almost all of (the etiquette) out the window and everybody is bunched up. You can't wait for one (slow) car on the restarts because you might lose eight or 10 spots before you know it."